htdocs/lib/upgrade.php

<?php
/**
 *
 * @package    mahara
 * @subpackage core
 * @author     Catalyst IT Ltd
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL version 3 or later
 * @copyright  For copyright information on Mahara, please see the README file distributed with this software.
 *
 */

defined('INTERNAL') || die();

/**
 * Class to use for installation exceptions
 */
class InstallationException extends SystemException {}

require_once('ddl.php');

/**
 * This function checks core and plugins for which need to be upgraded/installed
 *
 * Note: This function is sometimes executed during upgrades from
 * ancient databases.  Avoid rash assumptions about what's installed
 * or these upgrades may fail.
 *
 * @param string $name The name of the plugin to check. If no name is specified,
 *                     all plugins are checked.
 * @return mixed If a name is specified, an object will be returned with upgrade data
 *                     about the requested component (which can be "core", "local", or a plugin).
 *                     If the component desn't need to be updated, an empty array will be returned.
 *               If no name is specified, an array of such objects will be returned.
 *                     It will also include an array key "settings", which will be an array
 *                     that may contain metadata about the upgrade/install process.
 */
function check_upgrades($name=null) {

    $pluginstocheck = plugin_types();

    $toupgrade = array();
    $settings = array();
    $toupgradecount = 0;
    $newinstallcount = 0;
    $installing = false;
    $disablelogin = false;
    $newinstalls = array();

    require('version.php');
    if (isset($config->disablelogin) && !empty($config->disablelogin)) {
        $disablelogin = true;
    }
    // check core first...
    if (empty($name) || $name == 'core') {
        try {
            $coreversion = get_config('version');
        }
        catch (Exception $e) {
            $coreversion = 0;
        }
        $core = new stdClass();
        $core->to = $config->version;
        $core->torelease = $config->release;
        $core->toseries = $config->series;
        $toupgrade['core'] = $core;
        if (empty($coreversion)) {
            if (is_mysql()) { // Show a more informative error message if using mysql with skip-innodb
                // In MySQL 5.6.x, we run the command 'SHOW ENGINES' to check if InnoDB is enabled or not
                global $db;
                $result = $db->Execute("SHOW ENGINES");
                $hasinnodb = false;
                while (!$result->EOF) {
                    if ($result->fields['Engine'] == 'InnoDB' && ($result->fields['Support'] == 'YES' || $result->fields['Support'] == 'DEFAULT')) {
                        $hasinnodb = true;
                        break;
                    }
                    $result->MoveNext();
                }

                if (!$hasinnodb) {
                    throw new ConfigSanityException("Mahara requires InnoDB tables.  Please ensure InnoDB tables are enabled in your MySQL server.");
                }
            }
            $core->install = true;
            $installing = true;
        }
        else if ($config->version > $coreversion) {
            $corerelease = get_config('release');
            if (isset($config->minupgradefrom) && isset($config->minupgraderelease)
                && $coreversion < $config->minupgradefrom) {
                throw new ConfigSanityException("Must upgrade to $config->minupgradefrom "
                                          . "($config->minupgraderelease) first "
                                          . " (you have $coreversion ($corerelease)");
            }
            $toupgradecount ++;
            $core->upgrade = true;
            $core->from = $coreversion;
            $core->fromrelease = $corerelease;
        }
        else {
            // Core doesn't need to be upgraded. Remove it from the list!
            unset($toupgrade['core']);
        }
    }

    // If we were just checking if the core needed to be upgraded, we can stop here
    if ($name == 'core') {
        $toupgrade['core']->disablelogin = $disablelogin;
        return $toupgrade['core'];
    }

    if (!$installing && (empty($name) || $name == 'local')) {
        $localversion = get_config('localversion');
        $localrelease = get_config('localrelease');
        if (is_null($localversion)) {
            $localversion = 0;
            $localrelease = 0;
        }

        $config = new StdClass;
        require(get_config('docroot') . 'local/version.php');

        if ($config->version > $localversion) {
            $toupgradecount ++;
            $toupgrade['local'] = (object) array(
                'upgrade'     => true,
                'from'        => $localversion,
                'fromrelease' => $localrelease,
                'to'          => $config->version,
                'torelease'   => $config->release,
            );
        }

        if ($name == 'local') {
            $toupgrade['local']->disablelogin = $disablelogin;
            return $toupgrade['local'];
        }
    }

    $plugins = array();
    if (!empty($name)) {
        try {
            $bits = explode('.', $name);
            $pt = $bits[0];
            $pn = $bits[1];
            $pp = null;
            if ($pt == 'blocktype' && strpos($pn, '/') !== false) {
                $bits = explode('/', $pn);
                $pp = get_config('docroot') . 'artefact/' . $bits[0]  . '/blocktype/' . $bits[1];
            }
            validate_plugin($pt, $pn, $pp);
            $plugins[] = explode('.', $name);
        }
        catch (InstallationException $_e) {
            log_warn("Plugin $pt $pn is not installable: " . $_e->GetMessage());
        }
    }
    else {
        foreach ($pluginstocheck as $plugin) {
            $dirhandle = opendir(get_config('docroot') . $plugin);
            while (false !== ($dir = readdir($dirhandle))) {
                if (strpos($dir, '.') === 0 or 'CVS' == $dir) {
                    continue;
                }
                if (!is_dir(get_config('docroot') . $plugin . '/' . $dir)) {
                    continue;
                }
                try {
                    validate_plugin($plugin, $dir);
                    $plugins[] = array($plugin, $dir);
                }
                catch (InstallationException $_e) {
                    log_warn("Plugin $plugin $dir is not installable: " . $_e->GetMessage());
                }

                if ($plugin == 'artefact') { // go check it for blocks as well
                    $btlocation = get_config('docroot') . $plugin . '/' . $dir . '/blocktype';
                    if (!is_dir($btlocation)) {
                        continue;
                    }
                    $btdirhandle = opendir($btlocation);
                    while (false !== ($btdir = readdir($btdirhandle))) {
                        if (strpos($btdir, '.') === 0 or 'CVS' == $btdir) {
                            continue;
                        }
                        if (!is_dir(get_config('docroot') . $plugin . '/' . $dir . '/blocktype/' . $btdir)) {
                            continue;
                        }
                        $plugins[] = array('blocktype', $dir . '/' . $btdir);
                    }
                }
            }
        }
    }

    foreach ($plugins as $plugin) {
        $plugintype = $plugin[0];
        $pluginname = $plugin[1];
        $pluginpath = "$plugin[0]/$plugin[1]";
        $pluginkey  = "$plugin[0].$plugin[1]";

        if ($plugintype == 'blocktype' && strpos($pluginname, '/') !== false) {
            // sigh.. we're a bit special...
            $bits = explode('/', $pluginname);
            $pluginpath = 'artefact/' . $bits[0] . '/blocktype/' . $bits[1];
        }

        // Don't try to get the plugin info if we are installing - it will
        // definitely fail
        $pluginversion = 0;
        if (!$installing && table_exists(new XMLDBTable($plugintype . '_installed'))) {
            if ($plugintype == 'blocktype' && strpos($pluginname, '/')) {
                $bits = explode('/', $pluginname);
                $installed = get_record('blocktype_installed', 'name', $bits[1], 'artefactplugin', $bits[0]);
            }
            else {
                $installed = get_record($plugintype . '_installed', 'name', $pluginname);
            }
            if ($installed) {
                $pluginversion = $installed->version;
                $pluginrelease =  $installed->release;
            }
        }

        $config = new StdClass;
        require(get_config('docroot') . $pluginpath . '/version.php');
        if (isset($config->disablelogin) && !empty($config->disablelogin)) {
            $disablelogin = true;
        }

        if (empty($pluginversion)) {
            $newinstall = false;
            if (empty($installing) && $pluginkey != $name) {
                $newinstall = true;
            }
            $plugininfo = new StdClass;
            $plugininfo->install = true;
            $plugininfo->to = $config->version;
            $plugininfo->torelease = $config->release;
            if (property_exists($config, 'requires_config')) {
                $plugininfo->requires_config = $config->requires_config;
            }
            if (property_exists($config, 'requires_parent')) {
                $plugininfo->requires_parent = $config->requires_parent;
            }

            $classname = generate_class_name($plugintype, $pluginname);
            safe_require($plugintype, $pluginname);
            try {
                $classname::sanity_check();
            }
            catch (InstallationException $exc) {
                $plugininfo->to = get_string('notinstalled', 'admin');
                $plugininfo->torelease = get_string('notinstalled', 'admin');
                $plugininfo->errormsg = $exc->getMessage();
            }

            if ($newinstall) {
                $plugininfo->from = get_string('notinstalled', 'admin');
                $plugininfo->fromrelease = get_string('notinstalled', 'admin');
                $plugininfo->newinstall = true;
                $newinstallcount ++;
                $newinstalls[$pluginkey] = $plugininfo;
            }
            else {
                $toupgrade[$pluginkey] = $plugininfo;
            }
        }
        else if ($config->version > $pluginversion) {
            if (isset($config->minupgradefrom) && isset($config->minupgraderelease)
                && $pluginversion < $config->minupgradefrom) {
                throw new ConfigSanityException("Must upgrade to $config->minupgradefrom "
                                          . " ($config->minupgraderelease) first "
                                          . " (you have $pluginversion ($pluginrelease))");
            }
            $toupgradecount++;
            $plugininfo = new StdClass;
            $plugininfo->upgrade = true;
            $plugininfo->from = $pluginversion;
            $plugininfo->fromrelease = $pluginrelease;
            $plugininfo->to = $config->version;
            $plugininfo->torelease = $config->release;
            if (property_exists($config, 'requires_config')) {
                $plugininfo->requires_config = $config->requires_config;
            }
            if (property_exists($config, 'requires_parent')) {
                $plugininfo->requires_parent = $config->requires_parent;
            }

            $classname = generate_class_name($plugintype, $pluginname);
            safe_require($plugintype, $pluginname);
            try {
                $classname::sanity_check();
            }
            catch (InstallationException $exc) {
                $plugininfo->to = $config->version;
                $plugininfo->torelease = $pluginrelease;
                $plugininfo->errormsg = $exc->getMessage();
                $toupgrade[$pluginkey] = $plugininfo;

                continue;
            }

            $toupgrade[$pluginkey] = $plugininfo;
        }
    }

    // if we've just asked for one, don't return an array...
    if (!empty($name)){
        if (count($toupgrade) == 1) {
            $upgrade = new StdClass;
            $upgrade->name = $name;
            foreach ((array)$toupgrade[$name] as $key => $value) {
                $upgrade->{$key} = $value;
            }
            $upgrade->disablelogin = $disablelogin;
            return $upgrade;
        }
        else {
            return array();
        }
    }

    // Nothing needed to be upgraded or installed
    if (count($toupgrade) == 0) {
        if (!empty($name))
        $disablelogin = false;
    }

    // If we get here, it's because we have an array of objects to return
    uksort($toupgrade, 'sort_upgrades');
    $settings['disablelogin'] = $disablelogin;
    $settings['newinstallcount'] = $newinstallcount;
    $settings['newinstalls'] = $newinstalls;
    $settings['toupgradecount'] = $toupgradecount;
    $toupgrade['settings'] = $settings;
    return $toupgrade;
}

/**
 * Upgrades the core system to given upgrade version.
 *
 * @param object $upgrade   The version to upgrade to
 * @return bool             Whether the upgrade succeeded or not
 * @throws SQLException     If the upgrade failed due to a database error
 */
function upgrade_core($upgrade) {
    global $db;

    $location = get_config('libroot') . 'db/';

    db_begin();

    if (!empty($upgrade->install)) {
        install_from_xmldb_file($location . 'install.xml');
    }
    else {
        require_once($location . 'upgrade.php');
        xmldb_core_upgrade($upgrade->from);
    }

    set_config('version', $upgrade->to);
    set_config('release', $upgrade->torelease);
    set_config('series', $upgrade->toseries);
    bump_cache_version();

    if (!empty($upgrade->install)) {
        core_postinst();
    }

    db_commit();
    return true;
}

/**
 * Upgrades local customisations.
 *
 * @param object $upgrade   The version to upgrade to
 * @return bool             Whether the upgrade succeeded or not
 * @throws SQLException     If the upgrade failed due to a database error
 */
function upgrade_local($upgrade) {
    db_begin();

    require_once(get_config('docroot') . 'local/upgrade.php');
    xmldb_local_upgrade($upgrade->from);

    set_config('localversion', $upgrade->to);
    set_config('localrelease', $upgrade->torelease);
    bump_cache_version();

    db_commit();
    return true;
}

/**
 * Upgrades the plugin to a new version
 *
 * Note: This function is sometimes executed during upgrades from
 * ancient databases.  Avoid rash assumptions about what's installed
 * or these upgrades may fail.
 *
 * @param object $upgrade   Information about the plugin to upgrade
 * @return bool             Whether the upgrade succeeded or not
 * @throws SQLException     If the upgrade failed due to a database error
 */
function upgrade_plugin($upgrade) {
    global $db;

    $plugintype = '';
    $pluginname = '';

    list($plugintype, $pluginname) = explode('.', $upgrade->name);

    if ($plugintype == 'blocktype' && strpos($pluginname, '/') !== false) {
        list($artefactplugin, $blocktypename) = explode('/', $pluginname);
        $location = get_config('docroot') . 'artefact/' . $artefactplugin . '/blocktype/' . $blocktypename . '/db/';
        $function = 'xmldb_' . $plugintype . '_' . $blocktypename . '_upgrade';
    }
    else {
        $location = get_config('docroot') . $plugintype . '/' . $pluginname . '/db/';
        $function = 'xmldb_' . $plugintype . '_' . $pluginname . '_upgrade';
    }

    db_begin();

    if (!empty($upgrade->install)) {
        if (is_readable($location . 'install.xml')) {
            install_from_xmldb_file($location . 'install.xml');
        }
    }
    else {
        if (is_readable($location .  'upgrade.php')) {
            require_once($location . 'upgrade.php');
            if (!$function($upgrade->from)) {
                throw new InstallationException("Failed to run " . $function . " (check logs for errors)");
            }
        }
    }

    $installed = new StdClass;
    $installed->name = $pluginname;
    $installed->version = $upgrade->to;
    $installed->release = $upgrade->torelease;
    if ($plugintype == 'blocktype') {
        if (!empty($blocktypename)) {
            $installed->name = $blocktypename;
        }
        if (!empty($artefactplugin)) { // blocks come from artefactplugins.
            $installed->artefactplugin = $artefactplugin;
        }
    }
    if (property_exists($upgrade, 'requires_config')) {
        $installed->requires_config = $upgrade->requires_config;
    }
    if (property_exists($upgrade, 'requires_parent')) {
        $installed->requires_parent = $upgrade->requires_parent;
    }
    $installtable = $plugintype . '_installed';

    if (!empty($upgrade->install)) {
        insert_record($installtable,$installed);
    }
    else {
        update_record($installtable, $installed, 'name');
    }
    bump_cache_version();

    // postinst stuff...
    safe_require($plugintype, $pluginname);
    $pcname = generate_class_name($plugintype, $installed->name);

    if ($crons = call_static_method($pcname, 'get_cron')) {
        foreach ($crons as $cron) {
            $cron = (object)$cron;
            if (empty($cron->callfunction)) {
                throw new InstallationException("cron for $pcname didn't supply function name");
            }
            if (!is_callable(array($pcname, $cron->callfunction))) {
                throw new InstallationException("cron $cron->callfunction for $pcname supplied but wasn't callable");
            }
            $new = false;
            $table = $plugintype . '_cron';
            if (!empty($upgrade->install)) {
                $new = true;
            }
            else if (!record_exists($table, 'plugin', $pluginname, 'callfunction', $cron->callfunction)) {
                $new = true;
            }
            $cron->plugin = $pluginname;
            if (!empty($new)) {
                insert_record($table, $cron);
            }
            else {
                update_record($table, $cron, array('plugin', 'callfunction'));
            }
        }
    }

    if ($events = call_static_method($pcname, 'get_event_subscriptions')) {
        foreach ($events as $event) {
            $event = (object)$event;

            if (!record_exists('event_type', 'name', $event->event)) {
                throw new InstallationException("event $event->event for $pcname doesn't exist!");
            }
            if (empty($event->callfunction)) {
                throw new InstallationException("event $event->event for $pcname didn't supply function name");
            }
            if (!is_callable(array($pcname, $event->callfunction))) {
                throw new InstallationException("event $event->event with function $event->callfunction for $pcname supplied but wasn't callable");
            }
            $exists = false;
            $table = $plugintype . '_event_subscription';
            $block = blocktype_namespaced_to_single($pluginname);
            if (empty($upgrade->install)) {
                $exists = get_record($table, 'plugin' , $block, 'event', $event->event);
            }
            $event->plugin = $block;
            if (empty($exists)) {
                insert_record($table, $event);
            }
            else {
                update_record($table, $event, array('id' => $exists->id));
            }
        }
    }

    if ($activities = call_static_method($pcname, 'get_activity_types')) {
        foreach ($activities as $activity) {
            $classname = 'ActivityType' . ucfirst($plugintype) . ucfirst($pluginname) . ucfirst($activity->name);
            if (!class_exists($classname)) {
                throw new InstallationException(get_string('classmissing', 'error',  $classname, $pluginname, $plugintype));
            }
            // Add activity_type if it doesn't exist
            if (!get_record('activity_type', 'name', $activity->name, 'plugintype', $plugintype, 'pluginname', $pluginname)) {
                $activity->plugintype = $plugintype;
                $activity->pluginname = $pluginname;
                $activity->defaultmethod = get_config('defaultnotificationmethod') ? get_config('defaultnotificationmethod') : $activity->defaultmethod;
                $where = (object) array(
                    'name'       => $activity->name,
                    'plugintype' => $plugintype,
                    'pluginname' => $pluginname,
                );
                ensure_record_exists('activity_type', $where, $activity);
            }
        }
    }

     // install artefact types
    if ($plugintype == 'artefact') {
        if (!is_callable(array($pcname, 'get_artefact_types'))) {
            throw new InstallationException("Artefact plugin $pcname must implement get_artefact_types and doesn't");
        }
        $types = call_static_method($pcname, 'get_artefact_types');
        $ph = array();
        if (is_array($types)) {
            foreach ($types as $type) {
                $ph[] = '?';
                if (!record_exists('artefact_installed_type', 'plugin', $pluginname, 'name', $type)) {
                    $t = new StdClass;
                    $t->name = $type;
                    $t->plugin = $pluginname;
                    insert_record('artefact_installed_type',$t);
                }
            }
            $select = '(plugin = ? AND name NOT IN (' . implode(',', $ph) . '))';
            delete_records_select('artefact_installed_type', $select,
                                  array_merge(array($pluginname),$types));
        }
    }

    // install blocktype categories.
    if ($plugintype == 'blocktype' && get_config('installed')) {
        install_blocktype_categories_for_plugin($pluginname);
        install_blocktype_viewtypes_for_plugin($pluginname);
    }

    $prevversion = (empty($upgrade->install)) ? $upgrade->from : 0;
    call_static_method($pcname, 'postinst', $prevversion);

    db_commit();
    return true;
}

function core_postinst() {
    $status = true;

    // Attempt to create session directories
    $sessionpath = get_config('sessionpath');
    if (check_dir_exists($sessionpath)) {
        // Create three levels of directories, named 0-9, a-f
        $characters = array('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f');
        foreach ($characters as $c1) {
            if (check_dir_exists("$sessionpath/$c1")) {
                foreach ($characters as $c2) {
                    if (check_dir_exists("$sessionpath/$c1/$c2")) {
                        foreach ($characters as $c3) {
                            if (!check_dir_exists("$sessionpath/$c1/$c2/$c3")) {
                                $status = false;
                                break(3);
                            }
                        }
                    }
                    else {
                        $status = false;
                        break(2);
                    }
                }
            }
            else {
                $status = false;
                break;
            }
        }
    }
    else {
        $status = false;
    }

    $now = db_format_timestamp(time());
    // Set default search plugin
    set_config('searchplugin', 'internal');

    set_config('lang', 'en.utf8');
    set_config('installation_key', get_random_key());
    set_config('installation_time', $now);
    set_config('stats_installation_time', $now);

    // Pre-define SMTP settings
    set_config('smtphosts', '');
    set_config('smtpport', '');
    set_config('smtpuser', '');
    set_config('smtppass', '');
    set_config('smtpsecure', '');

    // XMLDB adds a table's keys immediately after creating the table.  Some
    // foreign keys therefore cannot be created during the XMLDB installation,
    // because they refer to tables created later in the installation.  These
    // missing keys can be created now that all the core tables exist.
    $table = new XMLDBTable('usr');
    $key = new XMLDBKey('profileiconfk');
    $key->setAttributes(XMLDB_KEY_FOREIGN, array('profileicon'), 'artefact', array('id'));
    add_key($table, $key);

    $table = new XMLDBTable('institution');
    $key = new XMLDBKey('logofk');
    $key->setAttributes(XMLDB_KEY_FOREIGN, array('logo'), 'artefact', array('id'));
    add_key($table, $key);

    // PostgreSQL supports indexes over functions of columns, MySQL does not.
    // We make use if this if we can
    if (is_postgres()) {
        // Improve the username index
        execute_sql('DROP INDEX {usr_use_uix}');
        execute_sql('CREATE UNIQUE INDEX {usr_use_uix} ON {usr}(LOWER(username))');

        // Add user search indexes
        // Postgres only.  We could create non-lowercased indexes in MySQL, but
        // they would not be useful, and would require a change to varchar columns.
        execute_sql('CREATE INDEX {usr_fir_ix} ON {usr}(LOWER(firstname))');
        execute_sql('CREATE INDEX {usr_las_ix} ON {usr}(LOWER(lastname))');
        execute_sql('CREATE INDEX {usr_pre_ix} ON {usr}(LOWER(preferredname))');
        execute_sql('CREATE INDEX {usr_ema_ix} ON {usr}(LOWER(email))');
        execute_sql('CREATE INDEX {usr_stu_ix} ON {usr}(LOWER(studentid))');

        // Only one profile view per user
        execute_sql("CREATE UNIQUE INDEX {view_own_type_uix} ON {view}(owner) WHERE type = 'profile'");
    }

    // Some more advanced constraints. XMLDB can't handle this in its xml file format
    execute_sql('ALTER TABLE {artefact} ADD CHECK (
        (owner IS NOT NULL AND "group" IS NULL     AND institution IS NULL) OR
        (owner IS NULL     AND "group" IS NOT NULL AND institution IS NULL) OR
        (owner IS NULL     AND "group" IS NULL     AND institution IS NOT NULL)
    )');
    execute_sql('ALTER TABLE {view} ADD CHECK (
        (owner IS NOT NULL AND "group" IS NULL     AND institution IS NULL) OR
        (owner IS NULL     AND "group" IS NOT NULL AND institution IS NULL) OR
        (owner IS NULL     AND "group" IS NULL     AND institution IS NOT NULL)
    )');
    execute_sql('ALTER TABLE {artefact} ADD CHECK (
        (author IS NOT NULL AND authorname IS NULL    ) OR
        (author IS NULL     AND authorname IS NOT NULL)
    )');
    execute_sql('ALTER TABLE {view_access} ADD CHECK (
        (accesstype IS NOT NULL AND "group" IS NULL     AND usr IS NULL     AND token IS NULL   AND institution IS NULL) OR
        (accesstype IS NULL     AND "group" IS NOT NULL AND usr IS NULL     AND token IS NULL AND institution IS NULL) OR
        (accesstype IS NULL     AND "group" IS NULL     AND usr IS NOT NULL AND token IS NULL AND institution IS NULL) OR
        (accesstype IS NULL     AND "group" IS NULL     AND usr IS NULL     AND token IS NOT NULL AND institution IS NULL) OR
        (accesstype IS NULL     AND "group" IS NULL     AND usr IS NULL     AND token IS NULL AND institution IS NOT NULL)
    )');
    execute_sql('ALTER TABLE {collection} ADD CHECK (
        (owner IS NOT NULL AND "group" IS NULL     AND institution IS NULL) OR
        (owner IS NULL     AND "group" IS NOT NULL AND institution IS NULL) OR
        (owner IS NULL     AND "group" IS NULL     AND institution IS NOT NULL)
    )');

    set_antispam_defaults();
    reload_html_filters();

    // Default set of sites from which iframe content can be embedded
    $iframesources = array(
        'www.youtube.com/embed/'                   => 'YouTube',
        'player.vimeo.com/video/'                  => 'Vimeo',
        'www.slideshare.net/slideshow/embed_code/' => 'SlideShare',
        'www.glogster.com/glog/'                   => 'Glogster',
        'www.glogster.com/glog.php'                => 'Glogster',
        'edu.glogster.com/glog/'                   => 'Glogster',
        'edu.glogster.com/glog.php'                => 'Glogster',
        'wikieducator.org/index.php'               => 'WikiEducator',
        'voki.com/php/'                            => 'Voki',
    );
    $iframedomains = array(
        'YouTube'      => 'www.youtube.com',
        'Vimeo'        => 'vimeo.com',
        'SlideShare'   => 'www.slideshare.net',
        'Glogster'     => 'www.glogster.com',
        'WikiEducator' => 'wikieducator.org',
        'Voki'         => 'voki.com',
    );
    update_safe_iframes($iframesources, $iframedomains);

    require_once(get_config('docroot') . 'lib/file.php');
    update_magicdb_path();

    return $status;
}

function core_install_lastcoredata_defaults() {
    global $USER;
    db_begin();
    $institution = new StdClass;
    $institution->name = 'mahara';
    $institution->displayname = 'No Institution';
    $institution->authplugin  = 'internal';
    $institution->theme  = 'default';
    $institution->priority = 0;
    insert_record('institution', $institution);

    $pages = site_content_pages();
    $now = db_format_timestamp(time());
    foreach ($pages as $name) {
        $page = new stdClass();
        $page->name = $name;
        $page->ctime = $now;
        $page->mtime = $now;
        $page->content = get_string($page->name . 'defaultcontent', 'install', get_string('staticpageconfigdefault', 'install'));
        $page->institution = 'mahara';
        insert_record('site_content', $page);
    }

    $auth_instance = new StdClass;
    $auth_instance->instancename  = 'Internal';
    $auth_instance->priority='1';
    $auth_instance->institution   = 'mahara';
    $auth_instance->authname      = 'internal';
    $auth_instance->id = insert_record('auth_instance', $auth_instance, 'id', true);

    // Insert the root user
    $user = new StdClass;
    $user->id = 0;
    $user->username = 'root';
    $user->password = '*';
    $user->salt = '*';
    $user->firstname = 'System';
    $user->lastname = 'User';
    $user->email = 'root@example.org';
    $user->quota = get_config_plugin('artefact', 'file', 'defaultquota');
    $user->authinstance = $auth_instance->id;

    if (is_mysql()) { // gratuitous mysql workaround
        $newid = insert_record('usr', $user, 'id', true);
        set_field('usr', 'id', 0, 'id', $newid);
        execute_sql('ALTER TABLE {usr} AUTO_INCREMENT=1');
    }
    else {
        insert_record('usr', $user);
    }

    // install the default layout options
    install_view_layout_defaults();

    require_once('group.php');
    install_system_profile_view();
    install_system_dashboard_view();
    install_system_grouphomepage_view();
    require_once('view.php');
    install_system_portfolio_view();

    require_once('license.php');
    install_licenses_default();

    require_once('skin.php');
    install_skins_default();

    // Insert the admin user
    $user = new StdClass;
    $user->username = 'admin';
    $user->salt = auth_get_random_salt();
    $user->password = crypt('mahara', '$2a$' . get_config('bcrypt_cost') . '$' . substr(md5(get_config('passwordsaltmain') . $user->salt), 0, 22));
    $user->password = substr($user->password, 0, 7) . substr($user->password, 7+22);
    $user->authinstance = $auth_instance->id;
    $user->passwordchange = 1;
    $user->admin = 1;
    $user->firstname = 'Admin';
    $user->lastname = 'User';
    $user->email = 'admin@example.org';
    $user->quota = get_config_plugin('artefact', 'file', 'defaultquota');
    $user->id = insert_record('usr', $user, 'id', true);
    set_profile_field($user->id, 'email', $user->email);
    set_profile_field($user->id, 'firstname', $user->firstname);
    set_profile_field($user->id, 'lastname', $user->lastname);
    handle_event('createuser', $user);
    activity_add_admin_defaults(array($user->id));
    db_commit();

    // if we're installing, set up the block categories here and then poll the plugins.
    // if we're upgrading this happens somewhere else.  This is because of dependency issues around
    // the order of installation stuff.
    install_blocktype_extras();
}

function core_install_firstcoredata_defaults() {
    // Install the default institution
    db_begin();

    set_config('session_timeout', 86400);
    set_config('sitename', 'Mahara');
    set_config('defaultregistrationexpirylifetime', 1209600);
    set_config('defaultaccountinactivewarn', 604800);
    set_config('creategroups', 'all');
    set_config('createpublicgroups', 'all');
    set_config('allowpublicviews', 1);
    set_config('allowpublicprofiles', 1);
    set_config('allowanonymouspages', 0);
    set_config('generatesitemap', 1);
    set_config('showselfsearchsideblock', 0);
    set_config('showtagssideblock', 1);
    set_config('tagssideblockmaxtags', 20);
    set_config('usersallowedmultipleinstitutions', 1);
    set_config('userscanchooseviewthemes', 0);
    set_config('anonymouscomments', 1);
    set_config('homepageinfo', 1);
    set_config('showonlineuserssideblock', 1);
    set_config('footerlinks', serialize(array('privacystatement', 'about', 'contactus')));
    set_config('nousernames', 0);
    set_config('onlineuserssideblockmaxusers', 10);
    set_config('loggedinprofileviewaccess', 1);
    set_config('dropdownmenu', 0);
    // Set this to a random starting number to make minor version slightly harder to detect
    set_config('cacheversion', rand(1000, 9999));
    set_config('watchlistnotification_delay', 20);

    // install the applications
    $app = new StdClass;
    $app->name = 'mahara';
    $app->displayname = 'Mahara';
    $app->xmlrpcserverurl = '/api/xmlrpc/server.php';
    $app->ssolandurl = '/auth/xmlrpc/land.php';
    insert_record('application', $app);

    $app->name = 'moodle';
    $app->displayname = 'Moodle';
    $app->xmlrpcserverurl = '/mnet/xmlrpc/server.php';
    $app->ssolandurl = '/auth/mnet/land.php';
    insert_record('application', $app);

    // insert the event types
    $eventtypes = array(
        'createuser',
        'updateuser',
        'suspenduser',
        'unsuspenduser',
        'deleteuser',
        'undeleteuser',
        'expireuser',
        'unexpireuser',
        'deactivateuser',
        'activateuser',
        'userjoinsgroup',
        'saveartefact',
        'deleteartefact',
        'deleteartefacts',
        'saveview',
        'deleteview',
        'blockinstancecommit',
        'deleteblockinstance',
        'addfriend',
        'removefriend',
        'addfriendrequest',
        'removefriendrequest',
        'creategroup',
        'loginas',
    );

    foreach ($eventtypes as $et) {
        $e = new StdClass;
        $e->name = $et;
        insert_record('event_type', $e);
    }

    // install the core event subscriptions
    $subs = array(
        array(
            'event'        => 'createuser',
            'callfunction' => 'activity_set_defaults',
        ),
        array(
            'event'        => 'createuser',
            'callfunction' => 'add_user_to_autoadd_groups',
        ),
        array(
            'event'         => 'blockinstancecommit',
            'callfunction'  => 'watchlist_record_changes',
        ),
        array(
            'event'         => 'deleteblockinstance',
            'callfunction'  => 'watchlist_block_deleted',
        ),
        array(
            'event'         => 'saveartefact',
            'callfunction'  => 'watchlist_record_changes',
        ),
        array(
            'event'         => 'saveview',
            'callfunction'  => 'watchlist_record_changes',
        ),
    );

    foreach ($subs as $sub) {
        insert_record('event_subscription', (object)$sub);
    }

    // Install the activity types. Name, admin, delay, allownonemethod, defaultmethod.
    $activitytypes = array(
        array('maharamessage',      0, 0, 0, 'email'),
        array('usermessage',        0, 0, 0, 'email'),
        array('watchlist',          0, 1, 1, 'email'),
        array('viewaccess',         0, 1, 1, 'email'),
        array('contactus',          1, 1, 1, 'email'),
        array('objectionable',      1, 1, 1, 'email'),
        array('virusrepeat',        1, 1, 1, 'email'),
        array('virusrelease',       1, 1, 1, 'email'),
        array('institutionmessage', 0, 0, 1, 'email'),
        array('groupmessage',       0, 1, 1, 'email'),
    );

    foreach ($activitytypes as $at) {
        $a = new StdClass;
        $a->name = $at[0];
        $a->admin = $at[1];
        $a->delay = $at[2];
        $a->allownonemethod = $at[3];
        $a->defaultmethod = $at[4];
        insert_record('activity_type', $a);
    }

    // install the cronjobs...
    $cronjobs = array(
        'auth_clean_partial_registrations'          => array('5', '0', '*', '*', '*'),
        'auth_clean_expired_password_requests'      => array('5', '0', '*', '*', '*'),
        'auth_handle_account_expiries'              => array('5', '10', '*', '*', '*'),
        'auth_handle_institution_expiries'          => array('5', '9', '*', '*', '*'),
        'activity_process_queue'                    => array('*/5', '*', '*', '*', '*'),
        'auth_remove_old_session_files'             => array('30', '20', '*', '*', '*'),
        'recalculate_quota'                         => array('15', '2', '*', '*', '*'),
        'import_process_queue'                      => array('*/5', '*', '*', '*', '*'),
        'export_process_queue'                      => array('*/6', '*', '*', '*', '*'),
        'submissions_delete_removed_archive'        => array('15', '1', '1', '*', '*'),
        'cron_send_registration_data'               => array(rand(0, 59), rand(0, 23), '*', '*', rand(0, 6)),
        'export_cleanup_old_exports'                => array('0', '3,15', '*', '*', '*'),
        'import_cleanup_old_imports'                => array('0', '4,16', '*', '*', '*'),
        'cron_site_data_weekly'                     => array('55', '23', '*', '*', '6'),
        'cron_site_data_daily'                      => array('51', '23', '*', '*', '*'),
        'cron_check_for_updates'                    => array(rand(0, 59), rand(0, 23), '*', '*', '*'),
        'cron_clean_internal_activity_notifications'=> array(45, 22, '*', '*', '*'),
        'cron_sitemap_daily'                        => array(0, 1, '*', '*', '*'),
        'file_cleanup_old_cached_files'             => array(0, 1, '*', '*', '*'),
        'user_login_tries_to_zero'                  => array('*/5', '*', '*', '*', '*'),
        'cron_institution_registration_data'        => array(rand(0, 59), rand(0, 23), '*', '*', rand(0, 6)),
        'cron_institution_data_weekly'              => array('55', '23', '*', '*', '6'),
        'cron_institution_data_daily'               => array('51', '23', '*', '*', '*'),
        'check_imap_for_bounces'                    => array('*', '*', '*', '*', '*'),
        'cron_event_log_expire'                     => array('7', '23', '*', '*', '*'),
        'watchlist_process_notifications'           => array('*', '*', '*', '*', '*'),
    );
    foreach ($cronjobs as $callfunction => $times) {
        $cron = new StdClass;
        $cron->callfunction = $callfunction;
        $cron->minute       = $times[0];
        $cron->hour         = $times[1];
        $cron->day          = $times[2];
        $cron->month        = $times[3];
        $cron->dayofweek    = $times[4];
        insert_record('cron', $cron);
    }

    $viewtypes = array('dashboard', 'portfolio', 'profile', 'grouphomepage');
    foreach ($viewtypes as $vt) {
        insert_record('view_type', (object)array(
            'type' => $vt,
        ));
    }
    db_commit();
}


/**
 * xmldb will pass us the xml file and we can perform any substitution as necessary
 */
function local_xmldb_contents_sub(&$contents) {
    // the main install.xml file needs to sub in plugintype tables.
    $searchstring = '<!-- PLUGIN_TYPE_SUBSTITUTION -->';
    if (strstr($contents, $searchstring) === 0) {
        return;
    }
    // ok, we're in the main file and we need to install all the plugin tables
    // get the basic skeleton structure
    $plugintables = file_get_contents(get_config('docroot') . 'lib/db/plugintables.xml');
    $tosub = '';
    foreach (plugin_types() as $plugin) {
        // any that want their own stuff can put it in docroot/plugintype/lib/db/plugintables.xml
        //- like auth is a bit special
        $specialcase = get_config('docroot') . $plugin . '/plugintables.xml';
        if (is_readable($specialcase)) {
            $tosub .= file_get_contents($specialcase) . "\n";
        }
        else {
            $replaced = '';
            // look for tables to put at the start...
            $pretables = get_config('docroot') . $plugin . '/beforetables.xml';
            if (is_readable($pretables)) {
                $replaced = file_get_contents($pretables) . "\n";
            }

            // perform any additional once off substitutions
            require_once(get_config('docroot') . $plugin . '/lib.php');
            if (method_exists(generate_class_name($plugin), 'extra_xmldb_substitution')) {
                $replaced  .= call_static_method(generate_class_name($plugin), 'extra_xmldb_substitution', $plugintables);
            }
            else {
                $replaced .= $plugintables;
            }
            $tosub .= str_replace('__PLUGINTYPE__', $plugin, $replaced) . "\n";
            // look for any tables to put at the end..
            $extratables = get_config('docroot') . $plugin . '/extratables.xml';
            if (is_readable($extratables)) {
                $tosub .= file_get_contents($extratables) . "\n";
            }
        }
    }
    $contents = str_replace($searchstring, $tosub, $contents);
}


/**
 * validates a plugin for installation
 * @throws InstallationException
*/
function validate_plugin($plugintype, $pluginname, $pluginpath='') {

    if (empty($pluginpath)) {
        $pluginpath = get_config('docroot') . $plugintype . '/' . $pluginname;
    }
    if (!file_exists($pluginpath . '/version.php')) {
        throw new InstallationException(get_string('versionphpmissing', 'error', $plugintype, $pluginname));
    }
    safe_require($plugintype, $pluginname);
    $classname = generate_class_name($plugintype, $pluginname);
    if (!class_exists($classname)) {
        throw new InstallationException(get_string('classmissing', 'error', $classname, $plugintype, $pluginname));
    }
    require_once(get_config('docroot') . $plugintype . '/lib.php');
    $funname = $plugintype . '_check_plugin_sanity';
    if (function_exists($funname)) {
        $funname($pluginname);
    }
}

/*
* the order things are installed/upgraded in matters
*/

function sort_upgrades($k1, $k2) {
    if ($k1 == 'core') {
        return -1;
    }
    else if ($k2 == 'core') {
        return 1;
    }
    else if ($k1 == 'firstcoredata') {
        return -1;
    }
    else if ($k2 == 'firstcoredata') {
        return 1;
    }
    else if ($k1 == 'localpreinst') {
        return -1;
    }
    else if ($k2 == 'localpreinst') {
        return 1;
    }
    else if ($k1 == 'localpostinst') {
        return 1;
    }
    else if ($k2 == 'localpostinst') {
        return -1;
    }
    else if ($k1 == 'lastcoredata') {
        return 1;
    }
    else if ($k2 == 'lastcoredata') {
        return -1;
    }
    // else obey the order plugin types returns (strip off plugintype. from the start)
    $weight1 = array_search(substr($k1, 0, strpos($k1, '.')), plugin_types());
    $weight2 = array_search(substr($k2, 0, strpos($k2, '.')), plugin_types());
    return ($weight1 > $weight2);
}

/** blocktype categories the system exports (including artefact categories)
*/
function get_blocktype_categories() {
    return array('shortcut', 'fileimagevideo', 'blog', 'general', 'internal', 'resume', 'external');
}

function install_blocktype_categories_for_plugin($blocktype) {
    if (!safe_require('blocktype', $blocktype, 'lib.php', 'require_once', true)) {
        // Block has been uninstalled or is missing, so no category data to enter.
        return;
    }
    $blocktype = blocktype_namespaced_to_single($blocktype);
    $catsinstalled = get_column('blocktype_category', 'name');
    db_begin();
    delete_records('blocktype_installed_category', 'blocktype', $blocktype);
    if ($cats = call_static_method(generate_class_name('blocktype', $blocktype), 'get_categories')) {
        foreach ($cats as $k=>$v) {
            if (is_string($k) && is_int($v)) {
                // New block with name => sortorder array.
                $cat = $k;
                $sortorder = $v;
            }
            else {
                // Legacy block with just categories, no sortorders. Give it the default sortorder.
                $cat = $v;
                $sortorder = PluginBlocktype::$DEFAULT_SORTORDER;
            }
            if (in_array($cat, $catsinstalled)) {
                insert_record('blocktype_installed_category', (object)array(
                    'blocktype' => $blocktype,
                    'category' => $cat,
                    'sortorder' => $sortorder,
                ));
            }
        }
    }
    db_commit();
}

function install_blocktype_viewtypes_for_plugin($blocktype) {
    safe_require('blocktype', $blocktype);
    $blocktype = blocktype_namespaced_to_single($blocktype);
    $vtinstalled = get_column('view_type', 'type');
    db_begin();
    delete_records('blocktype_installed_viewtype', 'blocktype', $blocktype);
    if ($viewtypes = call_static_method(generate_class_name('blocktype', $blocktype), 'get_viewtypes')) {
        foreach($viewtypes as $vt) {
            if (in_array($vt, $vtinstalled)) {
                insert_record('blocktype_installed_viewtype', (object)array(
                    'blocktype' => $blocktype,
                    'viewtype'  => $vt,
                ));
            }
        }
    }
    db_commit();
}

function install_blocktype_extras() {
    db_begin();

    $categories = get_blocktype_categories();
    $installedcategories = get_column('blocktype_category', 'name');
    $sort = empty($installedcategories) ? -1 : get_record_sql('SELECT MAX(sort) AS maxsort FROM {blocktype_category}')->maxsort;

    if ($toinstall = array_diff($categories, $installedcategories)) {
        foreach ($toinstall as $i) {
            insert_record('blocktype_category', (object)array('name' => $i, 'sort' => (++$sort)));
        }
    }

    db_commit();


    // poll all the installed blocktype plugins and ask them what categories they export
    if ($blocktypes = plugins_installed('blocktype', true)) {
        foreach ($blocktypes as $bt) {
            install_blocktype_categories_for_plugin(blocktype_single_to_namespaced($bt->name, $bt->artefactplugin));
            install_blocktype_viewtypes_for_plugin(blocktype_single_to_namespaced($bt->name, $bt->artefactplugin));
        }
    }
}

/**
 * Installs all the allowed column widths for views. Used when installing core
 * defaults, and also when upgrading from 1.7 to 1.8
 */
function install_view_column_widths() {
    require_once('view.php');

    $layout = new stdClass();
    $delayinserts = array();
    $x = 0;
    foreach (View::$basic_column_layouts as $column => $widths) {
        foreach ($widths as $width) {
            // If we're upgrading, then this width may already be present
            // from the conversion of an exising layout.
            if (!record_exists('view_layout_columns', 'widths', $width)) {
                $layout = new stdClass();
                $layout->columns = $column;
                $layout->widths = $width;
                insert_record('view_layout_columns', $layout);
            }
        }
    }
}

function install_view_layout_defaults() {
    db_begin();
    require_once('view.php');

    // Make sure all the column widths are present
    install_view_column_widths();

    // Fetch all the existing layouts so we can check below whether each default already exists
    $oldlayouts = array();
    $layoutrecs = get_records_assoc('view_layout', 'iscustom', '0', '', 'id, rows, iscustom');
    if ($layoutrecs) {
        foreach ($layoutrecs as $rec) {
            $rows = get_records_sql_assoc(
                    'select vlrc.row, vlc.widths
                    from
                        {view_layout_rows_columns} vlrc
                        inner join {view_layout_columns} vlc
                            on vlrc.columns = vlc.id
                    where vlrc.viewlayout = ?
                    order by vlrc.row',
                    array($rec->id)
            );
            if (!$rows) {
                // This layout has no rows. Strange, but let's just ignore it for now.
                log_warn('view_layout ' . $rec->id . ' is missing its row or column width records.');
                continue;
            }
            $allwidths = '';
            foreach ($rows as $rowrec) {
                $allwidths .= $rowrec->widths . '-';
            }
            // Drop the last comma
            $allwidths = substr($allwidths, 0, -1);
            $oldlayouts[$rec->id] = $allwidths;
        }
    }

    foreach (View::$defaultlayoutoptions as $id => $rowscols) {
        // Check to see whether it matches an existing record
        $allwidths = '';
        $numrows = 0;
        foreach ($rowscols as $row => $col) {
            if ($row != 'order') {
                $allwidths .= $col . '-';
                $numrows++;
            }
        }
        $allwidths = substr($allwidths, 0, -1);
        $found = array_search($allwidths, $oldlayouts);
        if ($found !== false) {
            // There's a perfect match in the DB already. Just make sure it has the right menu order
            if (isset($rowscols['order'])) {
                update_record(
                        'view_layout',
                        (object)array(
                                'id' => $found,
                                'layoutmenuorder'=>$rowscols['order']
                        )
                );
            }
            continue;
        }

        // It doesn't exist yet! So, set it up.
        $vlid = insert_record(
                'view_layout',
                (object)array(
                    'iscustom' => 0,
                    'rows' => $numrows,
                    'layoutmenuorder' => (isset($rowscols['order']) ? $rowscols['order'] : 0)
                ),
                'id',
                true
        );
        insert_record(
                'usr_custom_layout',
                (object)array(
                        'usr' => 0,
                        'group' => null,
                        'layout' => $vlid,
                )
        );

        foreach ($rowscols as $row => $col) {
            // The 'order' field indicates menu order if this layout is meant to be present
            // in the default layout menu
            if ($row == 'order') {
                continue;
            }

            // Check for the ID of the column widths that match this row
            $colsid = get_field('view_layout_columns', 'id', 'widths', $col);
            if (!$colsid) {
                // For some reason this layout_columns wasn't present yet.
                // We'll just insert it, but also throw a warning
                $colsid = insert_record(
                        'view_layout_columns',
                        (object) array(
                                'columns' => substr_count($col, ','),
                                'widths' => $col
                        ),
                        'id',
                        true
                );
                log_warn('Default layout option ' . $id . ' uses a column set that is not present in the list of default column widths.');
            }
            insert_record(
                    'view_layout_rows_columns',
                    (object)array(
                        'viewlayout' => $vlid,
                        'row' => $row,
                        'columns' => $colsid,
                    )
            );
        }
    }

    db_commit();
}

/**
 * Reload htmlpurifier filters from the XML configuration file.
 */
function reload_html_filters() {
    require_once('xmlize.php');

    $newlist = xmlize(file_get_contents(get_config('libroot') . 'htmlpurifiercustom/filters.xml'));
    $filters = $newlist['filters']['#']['filter'];
    foreach ($filters as &$f) {
        $f = (object) array(
            'site' => $f['#']['site'][0]['#'],
            'file' => $f['#']['filename'][0]['#']
        );
    }
    set_config('filters', serialize($filters));
    log_info('Enabled ' . count($filters) . ' HTML filters.');
}

function update_safe_iframe_regex() {
    $prefixes = get_column('iframe_source', 'prefix');
    if (!empty($prefixes)) {
        // We must generate a guaranteed valid regex here that's not
        // too slack.  It's easiest to whitelist a few characters, but
        // in future we may need to be more clever.  Admins who know
        // what they're doing, and need something fancy, can always
        // override this in config.php.
        foreach ($prefixes as $key => $r) {
            if (!preg_match('/^[a-zA-Z0-9\/\._-]+$/', $r)) {
                throw new SystemException('Invalid site passed to update_safe_iframe_regex');
            }
            if (substr($r, -1) == '/') {
                $prefixes[$key] = substr($r, 0, -1) . '($|[/?#])';
            }
        }

        // Allowed iframe URLs should be one of the partial URIs in iframe_source,
        // prefaced by http:// or https:// or just // (which is a protocol-relative URL)
        $iframeregexp = '%^(http:|https:|)//(' . str_replace('.', '\.', implode('|', $prefixes)) . ')%';
    }
    set_config('iframeregexp', isset($iframeregexp) ? $iframeregexp : null);
}

function update_safe_iframes(array $iframesources, array $iframedomains) {
    db_begin();

    delete_records('iframe_source_icon');
    foreach ($iframedomains as $name => $domain) {
        insert_record('iframe_source_icon', (object) array('name' => $name, 'domain' => $domain));
    }

    delete_records('iframe_source');
    foreach ($iframesources as $prefix => $name) {
        insert_record('iframe_source', (object) array('prefix' => $prefix, 'name' => $name));
    }

    update_safe_iframe_regex();
    db_commit();
}

/**
 * Use meaningful defaults for the antispam settings.
 */
function set_antispam_defaults() {
    set_config('formsecret', get_random_key());
    require_once(get_config('docroot') . 'lib/antispam.php');
    if(checkdnsrr('test.uribl.com.black.uribl.com', 'A')) {
        set_config('antispam', 'advanced');
    }
    else {
        set_config('antispam', 'simple');
    }
    set_config('spamhaus', 0);
    set_config('surbl', 0);
}

function activate_plugin_form($plugintype, $plugin) {
    return pieform(array(
        'name'            => 'activate_' . $plugintype . '_' . $plugin->name,
        'renderer'        => 'div',
        'elementclasses'  => false,
        'successcallback' => 'activate_plugin_submit',
        'class'           => 'form-inline form-as-button pull-left last',
        'jsform'          => false,
        'action'          => get_config('wwwroot') . 'admin/extensions/pluginconfig.php',
        'elements' => array(
            'plugintype' => array('type' => 'hidden', 'value' => $plugintype),
            'pluginname' => array('type' => 'hidden', 'value' => $plugin->name),
            'disable'    => array('type' => 'hidden', 'value' => $plugin->active),
            'enable'     => array('type' => 'hidden', 'value' => 1-$plugin->active),
            'submit'     => array(
                'type'  => 'button',
                'usebuttontag' => true,
                'class' => 'btn-default',
                'title' => ($plugin->active ? get_string('hide') : get_string('show')) . ' ' . $plugintype . ' ' . $plugin->name,
                'hiddenlabel' => true,
                'value' => $plugin->active ? get_string('hide') : get_string('show')
            ),
        ),
    ));
}

function activate_plugin_submit(Pieform $form, $values) {
    global $SESSION;
    if ($values['plugintype'] == 'blocktype') {
        if (strpos($values['pluginname'], '/') !== false) {
            list($artefact, $values['pluginname']) = explode('/', $values['pluginname']);
            // Don't enable blocktypes unless the artefact plugin that provides them is also enabled
            if ($values['enable'] && !get_field('artefact_installed', 'active', 'name', $artefact)) {
                $SESSION->add_error_msg(get_string('pluginnotenabled', 'mahara', $artefact));
                redirect('/admin/extensions/plugins.php');
            }
        }
    }
    else if ($values['plugintype'] == 'artefact' && $values['disable']) {
        // Disable all the artefact's blocktypes too
        set_field('blocktype_installed', 'active', 0, 'artefactplugin', $values['pluginname']);
    }
    set_field($values['plugintype'] . '_installed', 'active', $values['enable'], 'name', $values['pluginname']);
    $SESSION->add_ok_msg(get_string('plugin' . (($values['enable']) ? 'enabled' : 'disabled')));
    redirect('/admin/extensions/plugins.php');
}

// site warnings for the admin to consider
function site_warnings() {

    $warnings = array();

    // Warn about nasty php settings that Mahara can still sort of deal with.
    if (ini_get_bool('register_globals')) {
        $warnings[] = get_string('registerglobals', 'error');
    }
    if (!defined('CRON') && ini_get_bool('magic_quotes_gpc')) {
        $warnings[] = get_string('magicquotesgpc', 'error');
    }
    if (ini_get_bool('magic_quotes_runtime')) {
        $warnings[] = get_string('magicquotesruntime', 'error');
    }
    if (ini_get_bool('magic_quotes_sybase')) {
        $warnings[] = get_string('magicquotessybase', 'error');
    }

    // Check if the host returns a usable value for the timezone identifier %z
    $tz_count = preg_match("/[\+\-][0-9]{4}/", strftime("%z"));
    if ($tz_count == 0 || $tz_count == FALSE) {
        $warnings[] = get_string('timezoneidentifierunusable', 'error');
    }

    // Check for low security (i.e. not random enough) session IDs
    if ((int)ini_get('session.entropy_length') < 16) {
        $warnings[] = get_string('notenoughsessionentropy', 'error');
    }

    // Check noreply address is valid.
    if (!sanitize_email(get_config('noreplyaddress'))) {
        $warnings[] = get_string('noreplyaddressmissingorinvalid', 'error', get_config('wwwroot') . 'admin/site/options.php?fs=emailsettings');
    }

    // Check that the GD library has support for jpg, png and gif at least
    $gdinfo = gd_info();
    if (!$gdinfo['JPEG Support']) {
        $warnings[] = get_string('gdlibrarylacksjpegsupport', 'error');
    }

    if (!$gdinfo['PNG Support']) {
        $warnings[] = get_string('gdlibrarylackspngsupport', 'error');
    }

    if (!$gdinfo['GIF Read Support'] || !$gdinfo['GIF Create Support']) {
        $warnings[] = get_string('gdlibrarylacksgifsupport', 'error');
    }

    // Check file upload settings.
    $postmax       = ini_get('post_max_size');
    $uploadmax     = ini_get('upload_max_filesize');
    $realpostmax   = get_real_size($postmax);
    $realuploadmax = get_real_size($uploadmax);
    if ($realpostmax && $realpostmax < $realuploadmax) {
        $warnings[] = get_string('postmaxlessthanuploadmax', 'error', $postmax, $uploadmax, $postmax);
    }
    else if ($realpostmax && $realpostmax < 9000000) {
        $warnings[] = get_string('smallpostmaxsize', 'error', $postmax, $postmax);
    }

    if (ini_get('open_basedir')) {
        $warnings[] = get_string('openbasedirenabled', 'error') . ' ' . get_string('openbasedirwarning', 'error');
    }

    $sitesalt = get_config('passwordsaltmain');
    if (empty($sitesalt)) {
        $warnings[] = get_string('nopasswordsaltset', 'error');
    }
    else if ($sitesalt == 'some long random string here with lots of characters'
            || trim($sitesalt) === ''
            || preg_match('/^([a-zA-Z0-9]{0,10})$/', $sitesalt)) {
        $warnings[] = get_string('passwordsaltweak', 'error');
    }

    if (!extension_loaded('mbstring')) {
        $warnings[] = get_string('mbstringneeded', 'error');
    }

    if (get_config('dbtype') == 'mysql') {
        $warnings[] = get_string('switchtomysqli', 'error');
    }

    return $warnings;
}


/**
 * Increment the cache version number.
 * This is an arbitrary number that we append to the end of static content to make sure the user
 * refreshes it when we update the site.
 */
function bump_cache_version() {
    set_config('cacheversion', get_config('cacheversion') + 1);
}